Visibility is definitely one of the bigger regrets with this game, with your sprite and/or your hitbox easily getting lost in a game that asks you to dash directly into where the bullets are coming from.
Gameplay-wise, the game is generally more intended to be forgiving in the casual survival department (namely with the fact you can’t actually die, so the only way to lose is to run out of time - this in itself may have gone too far and probably should have had a lives system to make survival more meaningful), and emphasize difficulty and replay value with scoring instead.
Spamming dashes is quite effective for DPS/survival purposes, but not necessarily for scoring purposes since dashing at all resets the secondary multiplier gained from killing enemies with dashes. The intended (optimal?) strategy regarding dash kills is to start a big juicy dash kill multiplier by dashing through a group of weak enemies, then maintaining that combo by only shooting enemies until that combo expires since another dash will end the multiplier early. Only once the dash multiplier expires (or a better combo opportunity presents itself mid-combo) is it a good time to dash again. But overall, both circle-strafing and liberal dash usage are both valid strats with varying effectiveness.
Taking a hit is basically a non-issue when it comes to survival, but when it comes to scoring it can be problematic due to the short timers associated with the scoring systems now being taken up by your character being stunned. Originally the scoring penalty was even harsher by immediately killing the timers for both multipliers.
Though of course if scoring isn’t really your thing then none of this really matters (though as long as you could enjoy some parts of the game casually then it at least wasn’t a total wash); the intended audience is really those who like pushing/replaying short, arcadey games as far as they can.